Proportional spacing mechanism



Jan. 30, 1962 H. L. LAMBERT ETAL 3,018,870

PROPORTIONAL SPACING MECHANISM 5 Sheets-Sheet 2 Filed Aug. 18, 1959INVENTORS HARRY L. LAMBERT PAUL E PAGE vQm MGM

Jan. 30, 1962 H. LAMBERT ETAL 3,018,870

PROPORTIONAL SPACING MECHANISM 5 Sheets-Sheet 3 Filed Aug. 18, 1959INVENTORS HARRY L. LAMBERT PAUL F. PAGE Nhw Jan. 30, 1962 H. L. LAMBERTETAL PROPORTIONAL SPACING MECHANISM Filed Aug. 18, 1959 Sheets-Sheet 4 Eo r 211 L I g.

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INVENTORS HARRY L. LAMBERT PAUL F. PAGE Jan. 1962 H. L. LAMBERT ETAL3,01

PROPORTIONAL SPACING MECHANISM Filed Aug. 18, 1959 5 Sheets-Sheet 5INVENTORS 203 HARRY L. LAMBERT PAUL E PAGE 3,018,870 PRGPORTIUNALSPACING MECHANHSM Harry L. Lambert, West Hartford, and Paul F. Page,

Newington, Conn., assignors to Royal Mcliee Corporation, Port Chester,N.Y., a corporation of New York Filed Aug. 18, 1959, Ser. No. 834,59721.Claims. (Cl. 19784) This invention relates to an improved device forcontrolling the intermittent carriage feed motion of a typewriter or alike machine, and more particularly relates to an improved variablespacing mechanism for a typewriter carriage, and more specificallyrelates to a novel proportional escapement device for controlling theextent of incremental letter feed motion of a typewriter ca." riage inaccordance with the widths of the successive characters to be typed.

It is well recognized that the appearance of print work obtainable withtypewriters and like machines is greatly enhanced by providing some sortof means for controlling the extent of successve letter feed movementsof the typewriter carriage in accordance with the respective widths ofthe letters typed. The many prior attempts to provide apparatus for soproportioning the incremental displacements of the typewriter carriagehave not been entirely satisfactory either because they have beenunreliable and/ or too complex, or because they have been unable toefficiently cooperate with the other carriage control mechanism so as toproperly effect one or more of the desired carriage functions, such asback space, tabulation and/r banking operations. Furthermore those fewavailable devices for permitting the proportional spacing movement of atypewriter carriage are expensive and in operation tend to reduce themaximum permissible typing speed. The latter defect becomes significantwhen such prior art devices are used in electric typewriters themanually operated keys of which may be readily actuated at high speeds.

One object of the instant invention is to provide a proportional spacingmechanism for typewriters or like business machines which is reliablyeflicient and relatively inexpensive.

Another object of the instant invention is to provide an improvedproportional spacing mechanism for typewriters or the like having arelatively simple construction that inherently accommodates any reboundmovements of the typewriter carriage which may occur at the terminationof a tabulating or carriage return operation.

Another object of the invention is to provide an improved escapementmechanism for a typewriter carriage whereby a plurality of stop membersare each initially moved to a set position so as to be cooperable with anormally stationary stop and are subsequently selectively moved to unsetpositions so as to permit variable incremental letter feed movements ofthe typewriter carriage.

Another object of the invention is to provide an improved proportionalspacing mechanism for typewriters whereby a plurality of settable stopmembers are movably mounted on a rotatable disc or carrier and are eachsuccessively displaced from unset to set positions during theprogressive rotation of said disc produced by movement of the carriagein a letter feeding direction.

Another object of the invention is to provide a novel proportionalescapement mechanism for typewriters wherein a predetermined number ofstop members, each of which is initially positioned in set or carriagearresting position, are normally displaced to unset positions so as topermit the typewriter carriage to partake of successive normalincremental letter feed movements.

Another object of the invention is to provide a novel proportionalspacing mechanism for typewriters having a pluraltiy of movable stopmembers each of which is States atent initially moved to a set positionwhereby several of the set stop members may be moved to unset positionsby selectively operating a plurality of associated fingers during eachtyping operation of the machine.

A further object of the invention is to provide a novel proportionalescapement mechanism whereby a plurality of set stop members mounted ona rotatable carrier cooperate with a normally stationary stop which ismovable to an inoperative position during a tabulating movement of thetypewriter carriage, and which is restored to its operative positionwith the arresting of the carriage tabulating movement.

A further object of the invention is to provide a novel proportionalspacing mechanism for typewriters whereby a plurality of initially setstop members mounted on a rotatable carrier or disc cooperate with anormally stationary stop, said fixed stop being movable from a normaloperative position to an inoperative position during a tabulatingmovement of the typewriter carriage and in being restored to itsoperative position in response to the arresting of said carriage movesat least one of said stop members to an unset position.

Another object of the invention is to provide a novel proportionalspacing mechanism for typewriters whereby a plurality of settable stopmembers, which are mounted on a rotatable carrier so as to cooperatewith a normally stationary stop member, are successively moved to unsetpositions in response to disc rotation produced by a return movement ofthe typewriter carriage.

A still further object of the invention is to provide a novelproportional spacing mechanism for typewriters whereby a plurality ofnormally set stop members, which are mounted on a rotatable disc andwhich selectively cooperate with a normally stationary stop member, aresequentially moved to unset and set positions respectively in responseto a return movement of the typewriter carrlage.

Other objects and many of the attendant advantages of this inventionwill be readily appreciated as the same becomes better understood byreference to the following detailed description when considered inconnection with the accompanying drawings in which like referencenumerals designate like parts throughout the figures thereof andwherein:

FIGURE 1 is a central longitudinal view taken in partial section andshows the pertinent portions of the instant typewriter.

FIGURE 2 is a side elevational view taken in partial section and showsthe construction of the principal parts of the typewriter escapementmechanism.

FIGURE 3 is a front elevational view taken in partial section and showsthe apparatus illustrated in FIGURE 2.

FIGURE 4 is a fragmentary diametral view in partial section of theescapement carrier or disc and illustrates the set positions of the stopmembers on said disc.

FIGURE 5 is a plan view in partial section and shows the construction ofthe power operated permutation bails that control the operation of theescapement mechanism.

FIGURE 6 is an exploded perspective view showing an end portion of eachof the three permutation bails illustrated in FIGURE 5.

FIGURE 7 is a rear elevational view showing the interconnection betweenthe case shift linkage and the permutation bails.

FIGURE 8 is a diagrammatic sketch illustrating the normal disposition ofthe upper ends of the escapement controlling interposers and theescapement operating bail.

FIGURE 9 is an active side elevational view of a portion of theapparatus shown in FIGURE 1.

FIGURE 10 is a fragmentary perspective view illustrating the structuraland functional cooperation between the instant carriage tabulating andescapement mechanisms.

FIGURE 11 is a plan view illustrating the active positions of thepertinent parts of the escapement mechanism during a carriage tabulatingmovement.

FIGURE 12 is a plan view taken in partial section and shows the typeexpanding linkage associated with the instant escapement mechanism.

FIGURE 13 is a front elevational view showing the back space linkageassociated with the instant escapement mechanism.

The instant escapement mechanism is shown and will be described asembodied in an electric typewriter of the type presently being producedand sold by the Royal McBee Corporation, however it will be understoodthat this mechanism may be used in conjunction with other types ofmanual and electric typewriters and similar business machines havingcorresponding controls for their respectively associated intermittentlymovable carriages.

Referring to FIGURE 1 the pertinent parts of an electric typewriter areshown. It will be understood that unless otherwise stated the variousconventional parts or elements are suitably supported in the usualmanner on the machine frame. The main frame slidably mounts the recordsupporting carriage 11 for movement in letter feed and carriage returndirections under the action of the usual carriage drive means. Themachine is provided with the normal complement of type bars andrespectively associated sublevers, such as shown at 12 and 13respectively, which are selectively actuated by a power roll under thecontrol of the typewriter keys. As the type bars are successivelyoperated to type characters on the record sheet supported by thecylindrical platen 14, the carriage is permitted to intermittently movein a letter feed direction under the control of the proportionalescapement mechanism 15. This mechanism is operable to variably limitthe extent of each successive letter spacing movement of carriage 11 inaccordance with the width of the particular letter typed thereby greatlyimproving the appearance of the typed material as compared to thatproduced by typewriters affording uniform letter feed carriagemovements.

The carriage 11 is provided with a swingably mounted rack 16 which isnormally in engagement with a pinion 17 fixed on a shaft 20 that isrotatably mounted in the usual manner on the machine frame 10. Theproportional escapement mechanism controls the rotation of the pinion 17and hence through rack 16 determines the intermittent linear steppingmovements of said carriage 11 produced by the usual carriage springdrive means. Referring to FIGURES l-4, the escapement mechanism 15comprises a disc or carrier 21 which is rotatably fixed to the shaft andwhich has a plurality of equally circumferentially spaced and radiallyextending slots, such as at 22 of FIGURE 4, in which are respectivelydisposed stop members 23. The stop members 23 are radially retained insaid slots by means of a hoop 24 which is shrunk fit on and about theperiphery of said carrier 21; stop members 23 being free forlongitudinal sliding movement in said slots in a direction substantiallyparallel to the common axis of shaft 20 and carrier 21. The radiallyouter edge of each stop member 23 is provided with a pair of detentnotches 25, 26 which are adapted to cooperate with a toroidal coilspring 27 that is seated in a correspondingly contoured groove 30 formedabout the periphery of said carrier 21. As will be evident the spring 27in cooperation with notches 25, 26 will yieldably retain each stopmember 23 in either a set or operative position, as illustrated inFIGURE 4, or in an unset or inoperative position wherein the forward end31 of each stop member is substantially flush with the forward face 32of the disc or carrier 21. Referring particularly to FIGURES 3 and 12,the various stop members 23 are cooperable with either one of a pair ofsimilar normally stationary stops 33, 34 which are pivotally mounted bymeans of stud 35 on the usual escapement sub-frame 10a which comprises aportion of the main frame 10. The stops 33, 34 normally extend generallyparallel to the lower forward face 32, FIGURE 4, of said carrier 21 sothat their free ends lie in the circular path of travel of the forwardends of those stop members 23 which are in their respective setpositions illustrated in FIGURE 4. The abutment surface or shoulder 36at the free end of stop 33 is operative to control normal carriageletter feed operations and attention will first be directed to itsfunctional nature in the escapement mechanism; the purposes andfunctions of stop 34 being described in a subsequent part of thisdisclosure.

As will be evident, when any stop member 23 which is in its set oroperative position approaches and engages the abutment shoulder 36 ofstop 33, such will arrest further counter clockwise rotation 40, FIGURE3, of the carrier 21 and thus prevent the typewriter carriage fromfurther movement in a letter feed direction 41. Any stop member 23 whichis in its said unset or inoperative position as it approaches the outerend or abutment surface 36 of the normally stationary stop 33 will notbe intercepted by said stop but will arcuately bypass the latter therebypermitting the carriage spring drive means to move the carriage 11 insaid letter feed direction 41 until a subsequent stop member 23, whichis in the set position, encounters stop 33 thereby again arresting theletter feeding motion of the carriage.

Fixedly mounted on the said sub-frame 10a is a pair of cams 42 and 43,FIGURES 3 and 13, which are respectively disposed adjacent to the lowerportion of the rear face of the disc 21. Cam 42 is provided with aforwardly extending wedge shaped portion having tapered camming edges 44and 45, FIGURE 2, while cam 43 is provided with a forwardly extendingwedge shaped portion having tapered camming edges 46 and 47, FIGURE 3.These camming edges are positioned so as to lie in the path of travel ofthe rearward ends, such as 50, FIGURE 4, of those stop members 23 whichare in their respective unset or inoperative positions. When the disc orcarrier 2.1 is rotating in a letter feed or counter clockwise direction40, FIGURE 3, both of the camming surfaces 44 and 47 will be capable ofsuccessively displacing un-' set stop members 23 to their respective setpositions; on the other hand when said disc is rotating in a carriagereturn or clockwise direction 51, FIGURE 3, both of the camming surfaces45 and 46 will be capable of successively displacing unset stop members23 to their respective set positions.

As is best illustrated in FIGURE 12, the rearward edge of stop 33 isundercut so as to form an angularly disposed undercut camming surface 52which lies in the path of travel of the forward ends 31, FIGURE 4, ofthose stop members which are in their set positions whereby these stopmembers will be displaced to their respective unset positions whenmoving past said cam surface 52 in a carriage return or clockwisedirection 51 as seen in FIGURE 3.

It will be seen that during normal typing operations all of thesuccessive stop members 23 will be sequentially positioned in theirrespective set positions prior to approaching the immediate vicinity ofthe end 36 of stop 33 so that various ones of these set stops maythereafter selectively engage the said stop 33 during letter r spacingoperations. Normally one of the set stop members 23 is in operativeengagement with the said stop end 36 thereby preventing letter feedingmovements of said carriage, the next succeeding stop members to theleft, as seen in FIGURE 3, of said one stop member also being in theirrespective set positions. When a letter spacing operation is to beeffected said one set stop member together with one, two, three or fourof said next succeeding set stop members 23 will be displaced to theirunset positions, by means to be described, so that the typewritercarriage may move through a distance corresponding to the predeterminednumber of said set steps so displaced, this distance also correspondingto even multiples of the incremental circumferential pitch of thesuccessive stop members 23. As the disc or carrier 21 rotates in saidcounter clockwise direction 40, FIGURE 3, during the letter spacingoperation the stop members which were just displaced to unset positionswill by-pass stop 33 and the next following stop member 23 which is inthe set position will swing into operative engagement with said end 36of stop 33 thereby completing said letter spacing operation. It will benoted that the number of stop members 23 moved to set positions by thecamming surface 47 during this letter spacing operation will be the sameas the said predetermined number of stop members moved to unsetpositions to permit said letter spacing operation.

The means for simultaneously displacing a predetermined number of saidset stop members to unset positions will be described with particularreference to FIGURES 2 and 3. A shaft 60 is rotatably mounted on thesubframe a and pivotally supports four radially extending arms 61, 62,63 and 64. The upper end of arm 61 is bent off so as to form a stopmember engaging finger 65 which is of suificient width, as seen inFIGURE 3, to be capable of engaging the forward ends of three stopmembers and displacing the same to their respective unset positions. Asseen in FIGURE 3 the finger portion 65a is operatively associated withthe stop member 23 that is located immediately to the right of thenormally positioned stop end 36 While the remaining portion of finger 65is operatively associated with the two stop members 23 which are locatedimmediately to the left of said stop end 36. The upper ends of the arms62, 63 and 64- are bent off so as to form similar fingers 66, 67 and 68which are respectively adapted to engage and displace the forward endsof the third, fourth and fifth set stop members to the left, as seen inFIGURE 3, of the said end 36 of stop 33. Finger 68 is provided with alaterally bent off carry over lug 69 that overlies the forward face ofthe adjacent finger 67. Spacer bushings 7t), 71 and 72 are provided onsaid shaft 60 between the respective arms 61-64 so as to maintain thelatter in predetermined laterally spaced relation with respect to eachother and to their respectively associated stop members 23. Each of thearms 61-64 is provided with a rearwardly extending radial arm 73, FIGURE2, the free end of which is connected to a tension spring 74 that issuitably anchored on the machine frame 10a. Springs 74 yieldably biasarms 61-64 to their respective normal clockwise positions, as seen inFIGURE 2, determined by engagement of the upper edges of said radialarms 73 and the lower edge of a shaft 75, FIGURES 3 and 13, that isrotatably mounted in the sub-frame 10a, the stop member engaging fingers65-68 then being spaced a short distance in front of the forward ends 31of the six respectively associated stop members 23.

Selective actuation of the arms 6164 in a counter clockwise direction,FIGURE 2, for selectively displacing the associated stop members 23 totheir unset positions is obtained by means comprising an actuator bail80 which is rotatably secured to said shaft 60 by means of a suitableset screw 81, FIGURE 3, that is threaded through a bail hub portion 82.Bail 80 comprises a main body 83, a short depending leg 84 and anelongated depending leg 85. The lower end of depending leg 85 isarticulately and adjustably connected to a link 86 which is pivotallysecured to the shaft 87 fixed to the free end of the power operateduniversal bail arm 88 normally associated with the usual escapementmechanism of the typewriter. In that the purpose, construction andoperation of bail arm 88 is well known further structural discussionthereof here is unnecessary. It will be understood that when any one ofthe type bars of the machine is actuated the free end of the saiduniversal bail will be displaced through counter clockwise and clockwiseoscillatory strokes thereby correspondingly actuating the bail 83. Thebail body is maintained in proper axially spaced relation with respectto the said arms 61-64 by means of the spacerbushings 90 and 91 mountedon shaft 60. Mounted for vertical sliding move ment between therespective arms 62-64- and the bail body 83 is a set of three verticallymovable and selectively operable interposers 92, 93 and 94, FIGURE 3,that are maintained in substantially coplanar relation with respect tothe arms 61-64 respectively by means of a slotted comb 95 which issecured to the sub-frame 10a by any suitable means. The shapes andnormal vertical positional relation of the upper ends of saidinterposers are illustrated in the diagrammatic sketch of FIGURE 8. Theupper end of interposer 92 is coplanar with and adapted to engage theforward edge of the stop member setting arm 62, and is formed with anotch 101 and an abutment surface 102 which is normally positioned atthe same level as the bail body 83. Said surface 182 is adapted to beengaged and displaced by said bail body 83 and such action willcorrespond to a three incremental unit escapement of the typewritercarriage as will be described in a subsequent part of the specification.The upper end 103 of interposer 93 is coplanar with and adapted toengage the forward edge of the arm 63 and has an upper forwardly facingabutment surface 104 that is normally positioned below the level of thebail body 83. Said surface 104 is adapted, when elevated, to be engagedand displaced by the bail body 83 and such action will correspond to afour incremental unit escapement of the carriage 11. The upper end 105of-interposer 94 is coplanar with and adapted to engage the forward edgeof the stop member setting arm 64 and has an upper forwardly facingabutment surface 186 which is normally positioned below the level of thebail body 83. Said surface 106 is adapted, when elevated, to be engagedand displaced by the bail body 83 and such action will correspond to afive incremental unit escapement of the carriage as will be described.The arm 61 is provided with a forwardly extending projection 107,FIGURES 3 and 8, which is always located immediately to the rear of thebail body 83 and is adapted to be engaged and displaced by the bail body83 during each operative typing stroke of the typewriter, such actioncorresponding to a two unit escapement of the carriage. The threeinterposers 92-94 are selectively vertically operated in accordance withthe desired length of escapement travel of the typewriter carriage thatis to accompany each of the successively typed characters.

The various type bars of the machine control and operate means for soselectively actuating said interposers; such means being next describedin connection with FIG- URES 1, and 81(). As shown in FIGURE 1 eachsublever, such as 13, is provided with a depending projection 168 havinga lower camming edge or surface 19?. Mounted on the machine frameimmediately to the rear of the sub-levers is a pair of laterally spacedbrackets 110 and 111, FIGURE 5, the rearward ends of said bracketshaving coaxially disposed bail supporting stud shafts 112 and 113,respectively, fixed thereto which extend inwardly towards thelongitudinal center plane of the machine. Pivotally mounted on said studshafts are three permutation bails 120, 121 and 122; said bails beingprovided with pairs of nesting bent oif ears, such as illustrated at125- 125 126-126 and 127127 of FIGURES 5 and 6 which are suitablyapertured to pivotally engage the associated one of said stud shafts112, 113.

The bail is provided with several laterally spaced and forwardlyextending fingers 130, FIGURES 5 and 6, the outer ends of which lie inthe respective paths of travel of those sub-lever projections, such as108, that are respectively associated with the characters having fourincremental units of width, such as the letters E, w and U. The bail 121is provided with several similar forwardly extending fingers 131 whichare laterally interspersed with the various fingers 130. The outer endsof fingers 131 lie in the respective paths of travel of those subleverprojections that are respectively associated with the characters havingtwo incremental units of width such as the letters I, f and l. The bail122 has forwardly extending fingers 132 which are laterally interspersedwith the various other bail fingers. The outer ends of said fingers 132lie in the respective paths of travel of the sub-lever projectionsrespectively associated with those characters having five incrementalunits of Width such as the characters W, M, m and As will be noted someof the fingers 130, 131 are wider than the others, a single wide fingerbeing provided in each case here instead of having two separate butnarrower and immediately adjacent fingers where necessary. The bails120-122 are normally axially biased to the left, as seen in FIGURE 5, bymeans of a compression spring 140 which is disposed between the collar141 fixed to the stud shaft 112 and the adjacent face of the bent oifear 125 at the left side of said permutation bail 120. The right sidebracket 111, as seen in FIGURE 5, in addition to being formed with theupstanding stud shaft supporting portion 142 is provided with a lateralbent off portion 143, FIGURES and 7, on which is pivotally mounted abell crank 144. The upper end 145 of one leg of bell crank 144 isdisposed immediately adjacent the inner face of a rearward extension 146of said bent off ear 127 of bail 121. The outer end of the other bellcrank leg is provided with a bent off portion 147 which is adjustablythreadedly engaged by an abutment screw 150 having an operativelyassociated lock nut 151. The upper end of said abutment screw isdisposed beneath the lower face of a bracket 152 that is fixed to theside of the usual power operated case shift link 153 which verticallydisplaces the typewriter segment 154. The construction and operation oflink 153 is conventional in nature and needs no further explanationhere. In that the action of said spring 140 is to yieldably urge theupper end of said screw 150 into engagement with the said lower face ofthe bracket 152, it will be evident that the axial position of the threenested bails 120-122 will be determined by the position of the segment154 and the engagement of set screw 150 with the bracket 152. As will beevident when the segment is in its normal elevated position forpermitting typing of lower case characters the bails 120-122 will bemoved to and yieldably retained in a left hand position, as seen in FIG-URE 5, under the action of spring 140. In this condition of the bailsthe various sub-lever projections such as 108, associated with the two,four and five unit width characters will be operative to engage one setof the said bail fingers 130, 131 and 132 respectively. Here there willbe no bail fingers aligned with the type bar projections associated withthe three unit width characters such as b, h and 5. When the case shiftmechanism is operated and the segment is lowered, as illustrated byarrow 155, FIGURE 7, to a position for permitting the typing of uppercase characters, the bell crank 144 will be rotated in a counterclockwise direction, FIGURE 7, thereby shifting said bails to a righthand position as indicated by arrow 156, FIGURE 5. In this condition ofthe bails the various sub-lever projections, such as 108, associatedwith the 2, 4 and 5 unit width characters will again be operative toengage another set of the said bail fingers 130, 131 and 132respectively. As before there will be no bail fingers aligned with thetype bar projections associated with the upper case three unit widthcharacters such as 6],! is! i#.!7

As best illustrated in FIGURES 1 and 5 the three bails 120, 121, and 122are respectively provided with centrally located and rearwardlyextending projections 170, 171 and 172 to which are respectively fixedlysecured the rearwardly extending arms 173, 174 and 175. The rearwardends of the bail arms 173, 174 and 175 are respectively articulatelyconnected to the lower ends of the said interposers 92, 93 and 94. Eachof the bails 120-122 is biased in a counter clockwise direction by meansof a spring 176 which is suitably anchored to the machine frame. Thenormal position of the bails -122, as shown in FIGURE 1, is determinedby engagement of the lower edges of said arms 173-175 with the crossshaft 177 mounted in the frame of the machine.

In the operation of the above described apparatus the typewriter segment154 will normally be in its upper or FIGURE 1 position so as to permitthe typing of lower case characters. It will be recalled that thetypewriter carriage 11 is normally restrained from moving in a letterfeed direction 41, FIGURE 3, by that stop member 23 which is in its setposition and which is in engagement with the end 36 of the normallystationary stop 33. Here, in that there are no bail fingers -132 whichare aligned with and adjacent to the various camming edges such as 109of the sub-lever projections associated with the three unit widthcharacters, when any one of said three unit characters is typed none ofthe bails 120-122 will be rotated and hence none of the interposers92-94 will be vertically displaced from the respective normal positionsillustrated in FIGURE '8. Thus when the universal escapement bail 88swings in a counter clockwise direction, as seen in FIGURE 1, throughthe forward stroke of its cyclic oscillatory motion, link 86 will causebail 85 to rock in a counter clockwise direction so that the bail body83 engages both the said forward surface 102, FIG- URE 8, of interposer92 and the laterally adjacent shoulder 107 on the said arm 61. Theresultant pivotal movement of the stop member engaging fingers 65 and66, FIGURES 2 and 3, will serve to displace to unset positions thosethree set stop members 23 which are dis posed immediately to the left,FIGURE 3, of the abutment surface 36 of said normally stationary stop33. When this occurs the carriage is free to move in said letter feeddirection 41, FIGURE 3, and the carrier or disc 21 will be therebyrotated in a counter clockwise direction 40 until the next set stop 23swings into engagement with the said stationary stop 33. As will bapparent the extent of this rotational movement of carrier 21 will bethree times the peripheral pitch distance between the adjacent stopmembers 23 and hence the extent of resultant movement of the typewritercarriage 11 will correspond to the three incremental units of width ofthe lower case character just typed. As soon as the said three stopmembers have been displaced to unset positions by said fingers 65 and66, the universal escapement bail arm 88 and bail 80 will immediatelycommence their clockwise strokes, FIGURE 2, so as to permit theassociated springs 74 to swing the said fingers 65, 66 out of theoperative path of travel of the leftwardly adjacent stop members 23 andback to their respective normal positions. At the completion of thereturn stroke of the actuated type bar the various parts will berestored to their normal FIGURE 1 positions.

When a lower case character having two incremental units of width istyped the camming edge, such as 109, of. the associated sub-leverprojection will engage one of the fingers 131 so as to rock the bail 121in a clockwise direction, FIGURE 1, thereby elevating the interposer 92to an extent sufficient to place the surface 102 thereof above theoperative path of travel 83a, FIGURE 8 of the bail body 83. As a resultthe bail body 83 which swings in the counter clockwise direction, asseen in FIGURE 2, during the forward printing stroke of the type barwill engage only the said shoulder 107 formed on the arm 61 therebycausing the stop member engaging finger 65 to displace two set stopmembers 23 to their respective unset positions; these two stops beingfirst, that stop member which is in engagement with the stop 33 andsecondly, that stop member immediately to the left thereof as seen inFIGURE 3. This action will free the carriage for movement in the letterfeeding direction 41 through a distance corresponding to the twoincremental unit width of the character just typed; the associatedpermutation bail, interposer, sub-lever, etc., cooperatively completingtheir operative strokes in a manner similar to that described above forthe typing of three incremental unit width characters. When a lower casecharacter having a four incremental unit width is typed the cammingedge, such as 109, of the associated sub-lever projection will engageone of the fingers 130 as actively shown in FIGURE 9, so as to rock thebail 120 and thereby elevate interposer 93. As a result the interposers92 and 93, and the arm 61 will be rocked by the said motion 83a of bailbody 83 so that the stop member engaging fingers 65, 66 and 67 willcollectively displace four stop members 23 to unset positions. This willfree the carriage for movement in a letter feed direction to an extentcorresponding to the four incremental unit width of the character justtyped. When a lower case character having five incremental units ofwidth is typed the camming edge, such as 109, of the associated subleverprojection will engage one of the fingers 132 so as to rock bail 122which will elevate the interposer 94 to an extent sufiicient to placethe surface 106 in the operative path of travel 83a of the bail body 83.Thus the motion of the bail body 83 will displace the arm 61, theinterposer 92, and interposer 94, so that the stop member settingfingers 65, 66, 67 and 68 collectively displace five of the stop membersto unset positions, said finger 67 being operative through said carryover lug 69. It will be understood that in each of the above describedoperations the universal bail 88 will move through the arcuate returnportion of its cyclic oscillatory motion immediately after the variousfingers 65, 66, 67 and/ or 68 have displaced the desired number of stopmembers 23 to unset positions so that fingers are thereby immediatelywithdrawn from the path of movement of the following set stop members 23and will not interfere with the ensuing movement of the latter.

When the case shift mechanism of the typewriter is operated to permittyping of upper case characters the bails 120-122 will be shifted totheir right hand positions, FIGURE 5, so that again none of the bailfingers 130-132 are positioned to cooperate with the sub-leverprojections respectively associated with the characters having threeincremental units of width. The operations of the bail 80 and therespective interposers 9294 for the typing of 2, 3, 4 and 5 unit widthupper case characters respectively correspond to that just described forthe typing of 2, 3, 4 and 5 unit width lower case characters. When thesegment is elevated by operation of the case shift mechanism so as toagain permit typing of lower case characters, the bails 120422 will berestored to their normal left hand axial positions, FIGURE 5, under theaction of spring 140.

As the varaible width characters are successively typed the typewritercarriage 11 letter feeds to the left as seen in FIGURE 3 until arrestedby the right hand margin stop 190, FIGURE 10, of the machine, whereafterit is necessary to displace the carriage through a return stroke theextent of which is determined by the position of the usual left handmargin stop. In that the rack 16 remains in engagement with the pinion17 during carriage return movements the carrier or disc 21 will berotated in a clockwise direction 51, FIGURE 3. During this action anystop members 23 which are not in their set positions will besuccessively moved to such positions by the camming edge 46, FIGURES 3and 11, of cam 43. Immediately thereafter these set stop members aresuccessively displaced to their respective unset positions as they wipepast the said tapered undercut camming surface 52, FIGURE 12, of saidstop 33. These unset stops are then successively displaced to theirrespective set positions by means of the said tapered camming edge 45,FIGURE 2, of cam 42. This action continues until the end of the returntravel whereupon the usual carriage spring drive means will return thecarriage a short distance in a letter feed direction until the last stopmember 23' just moved to the set position by said camming edge 45 of cam42 swings in a counterclockwise direction, FIGURE 3, into operativeengagement with the end or abutment shoulder 36 of said stop 33preparatory for typing a new line of print. It will be noted that thearcuate distance between said last set stop member and said stop end 36is always the same, hence for any given setting of the left hand marginstop the carriage, after completing a return movement, will always cometo rest in the same predetermined columnar position thereby insuring aneven left hand margin for the typed material. This inherentcharacteristic of operation of the instant apparatus is very beneficialin that it avoids the necessity of having to provide additional orspecial means for overcoming the well known problem of carriage reboundthat normally occurs at the end of most carriage return strokes.

Means are provided in the instant escapement mechanism for expanding thecharacters that are typed, i.e. each letter feeding movement ispermitted to be longer than usual so that the spaces between thesuccessively typed characters are greater than normal. Referring toFIGURES 3, 10, 11 and 12 it will be seen that the second normallystationary stop 34 previously referred to is provided with an abutmentsurface or end 200 which is normally operatively disposed in the path oftravel of the set stop members 23 but which is offset to the right,FIGURE 3, from said stop end 36 a distance approximately correspondingto the circumferential pitch of said stop members 23. As will be evidentwhen the stop 33 is swung outwardly, counter clockwise as seen in FIG-URES 10 and 11, the end 200 of stop 34 will become operative to arrestthe letter feeding movements of the carriage 11. When several stopmembers 23 are to be moved to unset positions to permit a letter feedingmovement of the carriage, the stop member setting arm 61, FIGURE 3, andits associated fingers 65 and 65a will always displace those three setstop members which are immediately to the left, FIGURE 3, of theabutment surface or end 200 of the said second normally stationary stop34. Here the lengths of the carriage displacements corresponding to thenormal typing of characters having 2, 3, 4 and 5 incremental units ofwidth will now be 3, 4, 5 and 6 incremental units respectively. Thus thedistance between the successively typed characters will be increased byan amount corresponding to the operative horizontal offset distancebetween the stop ends 36 and 200. The extent of such offset distance isslightly less than the circular pitch of the successive stop members 23.

The means for swinging the normally stationary stop 33 away from thecarrier 21 to permit expanded typing comprises an upper toggle linkage202, FIGURE 12, said linkage comprising a bell crank 203 which ispivotally mounted by means of stud 204 to a bracket 205 secured by anysuitable means to the escapement frame 10a. The outer end of one arm ofhell crank 203 is articulately connected to one end of a link 206 thatis pivotally connected by a stud 207 to the outer end of the radiallydisposed arm 209 formed on said stop 33. The outer end of the other armof the bell crank 203 is articulately connected to one arm of a bellcrank 210 by a link 211 while the other arm of hell crank 210 isarticulately connected to a bell crank 212 by means of a link 213 havingan elongated slot 214 formed therein. The forwardly extending arm ofbell crank 213 projects through a suitable stepped slot 215 formed inthe front panel 216 of the typewriter and, as will be apparent, bymanually adjustably positioning bell crank handle 217 the normallystationary stop 33 may be swung from and to the operative position shownin FIGURE 10 to and from the inoperative position shown in FIGURE 12. Aspring 220, operatively secured between the bell crank 203 and a stud221 fixed to said bracket 205, rotatably biases bell crank 203 so as tourge and lock the stop 33 towards and in its operative FIGURE 10position. As long as stop 33 is so locked in its operative position theabove described normal typing operations may be carried out. On theother hand when stop 33 is retained in its inoperative position by theshifting of the manually operable bell crank 212 the typed material willbe expanded. When said bell crank 212 is restored to its normalposition, FIGURE 10, spring 220 will restore stop 33 and the associatedlinkage to normal positions for subsequent normal typing operatlons.

The instant escapement mechanism 15 is adapted to cooperate with thecarriage tabulating linkages of the typewriter. When a tabulatingcarriage movement is to take place both of the normally stationary stops33 and 34, FIGURE 3, are swung away from the carrier or disc 21, asillustrated in FIGURE 11, so as to permit the carriage rack 16, whichremains in engagement with the pinion 17 during said tabulatingmovement, to rotate the carrier 21 in a counter clockwise direction 40,FIG- URE 3. As is best seen in FIGURES 11 and 12, the lower stop 34 isprovided with an upstanding stud 225 which is disposed immediately tothe rear of the said tapered undercut surface 52 of the upper stop 33.The forwardly extending projection 226, FIGURES l and 12, of stop 34 isarticulately connected to a bell crank 227 by means of a link 230; bellcrank 227 being rotatably mounted on said stud 204, FIGURES 3 and 12.Bell crank 227 is rotatably biased in a counter clockwise direction,FIGURE 12, by means of a spring 231 which is operatively secured betweenthe bell crank stud 232 and the said stud 221 fixed to said bracket 205,thereby normally maintaining the stop 34 in its clockwise operativeposition shown in FIGURE 12. The operative position of the stop 34 andhence also, through said stud 225, the operative position of stop 33 isdetermined by the engagement of the rearwardly extending leg of hellcrank 227 with the abutment screw 233 fixed to said bracket 205, FIGURE12. When in this operative posi tion the toggle connection between bellcrank 203 and stop 33 and the toggle connection between bell crank 227and stop 34 are in their locked conditions. Bell crank 227 isarticulately connected to a lever 234 by means of a link 235. It will beapparent from FIGURE 11 that when lever 234 is pivoted in a counterclockwise direction about its pivot stud 236 the stop 34 will swing awayfrom the carrier 21 against the action of spring 231 thereby, throughsaid upstanding stud 225, correspondingly swinging the stop 33 againstthe action of the spring 220, as illustrated in FIGURE 11. Under theseconditions neither of the stops 33, 34 will be effective to impede theswinging movement of any of the set stop members 23 and hence thecarrier 21 will be free to rotate thereby permitting the carriage 11 topartake of a tabulating movement until stopped by the action of theusual tabulation arresting means whereupon the stops 33 and 34 will beurged by springs 220, 231 toward their respective operative positionsshown in FIGURE so as to resume letter feed control of the carriage aswill be more fully described below.

The essential elements of the conventional tabulating arresting meansfor the instant carriage 11 are fragmentarily shown in FIGURE 10 andwill be briefly described to an extent sufiicient to indicate the natureof the structural and functional cooperation between such and theescapement mechanism 15. To initiate a tabulating movement of thecarriage the power operated link 250 is moved forwardly thereby rockingthe crank plate 251 and its supporting shaft 252. During this action theupwardly extending arm 253 of said plate moves along the left edge,FIGURE 10, of the clockwise spring biased pivoted lever 254; the wallsdefining the lever notch 255 finally swinging into detenting engagementwith said arm 253 as shown in FIGURE 11. During this travel the arm 253will engage the angularly disposed camming edge 256 of said lever 234and swing the latter in a counter clockwise direction to thereby swingthe stop 34, and the stop 33 if the latter has not already been swung toits inoperative position for expanded typing, away from carrier 21 sothat the carriage 11 is free to cornxnence a tabulating movement. Whenthe plate 251 and shaft 252 are so rocked the arm 260 secured to thecentral part of the shaft will be arcuately displaced so as to swinglever 261 in a clockwise direction through link 262. The lever 261 isfixed to the shaft 263 which is pivotally and axially movably mounted onthe machine frame 10. The clockwise movement of lever 261 serves toswing the upper blade portion 264 of the lever into the path of travelof any of those tab stops 265 which have been moved to a set position.During the tabulating movement of the carriage the various stop members'23 of the escapement mechanism will be moved to and remain in theirrespective set positions as they swing counter clockwise, FIGURE 10,past the now inoperatively positioned stops 33, 34. This tabulatingmovement will continue until one of the tab stops 265 which has beenpreviously moved to said set" position engages the upper blade portion264 of lever 261. This will cause an axial movement of lever 261 andsuch will, through the interconnecting link 266, serve to pivot lever254 in a counter clockwise direction, FIGURE 10, against the action ofspring 267. This rotative displacement of lever 254 will release theplate 251 and the arm 253 for rearward pivotal movement from thedetented position of FIGURE 11 to the normal position of FIGURE 10. Asthe arm thus rides back past the camming edge 256 of lever 234, thelatter will thereby be permitted to swing in a clockwise direction,FIGURE 11, under the action of spring 231 thus allowing the bell crank227 to swing into engagement with said stop positioning screw 233,FIGURE 10, so as to again operatively position said stops 33, 34 withrespect to the carrier 21 and stop members 23. It will be noted thatduring the terminal portion of this clockwise restoring movement, FIGURE10, of the stop 33 the latter will engage one or more of the set stopmembers 23 of the now arrested carrier 21 and will displace said stopmembers to unset positions so that the stop end 36 will again beoperatively positioned in the path of travel of the next following setstop member.

When the plate 251 and shaft 252 are pivotally .restored to their normalpositions as above described the upper blade portion 264 of said lever261 will swing rearwardly to its inoperative position, FIGURE 10, out ofthe path of travel of the various set tab .stops 265. Thus the arrestedposition of the carriage determined by the operation of the tabulationarresting mechanism will be maintained by engagement with stop end 36 ofthat set stop member 23 which is next to the last stop member displacedto unset position by the restoration of said stop 33 to its operativeposition. The relative timed sequence of movement of lever 261 and thestops 33, 34 is such that the former moves into and out of the said pathof travel of the tab stops just before and after the stops 33, 34 moveout of and into the said path of travel of said stop members 23,respectively, whereby control of the carriage movement in a letter feeddirection alternately changes from and to the escapement mechanism 15and the above described tabulation control linkage. As will be apparentonly the stop 34 will be pivotally displaced and operatively associatedand disassociated with the stop members 23 during tabulating operationswhen the escapement mechanism is conditioned for expanded typing asabove described. It will be noted that in the instant arrangement thereis no connecting linkage which, as in the usual case, acts to lift thecarriage rack 16 out of engagement with the pinion 17 when a tabulatingmovement is initiated.

The inherent nature of operation of the instant escapement mechanismovercomes the long standing problem involving carriage tabulatingrebound caused by the impact of the set tab stop with the tab stoparresting blade. It will be seen from FIGURE that when stop 33 isrestored to its operative position after completion of a tabulatingmovement of the carriage, if there is any carriage rebound there will bean accompanying clockwise rotation of carrier 21. This however will notprevent the stop member 23, which was just previously in operativeengagement with the stop end 36, from again engaging said stop end aftersaid rebound in that during the relatively small clockwise reboundrotation of carrier 21 any stop members 23 which move past the undercutcam surface 52 and the stop end 36 will be displaced to unset positionsand will not subsequently prevent said operative set stop member fromre-engaging stop end 36 after completion of the carriage reboundmovement. this way the tabulated positions of the typewriter carriagewill always correspond to the respective predetermined columnarpositions determined by the respective tab stops which are in setposiitons.

A tab brake is provided with the instant apparatus so that thetypewriter carriage may be yieldably restrained from acquiring excessivespeeds during tabulating movements. Referring to FIGURE 11 there isshown a brake arm 275 which is pivotally mounted on the escapement subframe 10a by means of a stud 276. Secured to the free end of brake arm275 is a friction pad 277 which is made of leather or other suitablematerial and which is adapted to be pressed against the rearward face278, FIGURE 4, of the rotatable disc or carrier 21. Also rotatablymounted on stud 276 is a lever 280 which is articulately connected totab lever 234 by means of a link 281 and which is yieldably connected tosaid brake arm 275 by means of a tension spring 282. The clockwise limitof rotation of lever 280 with respect to brake arm 275 is determined byengagement of the left edge, FIGURE 11, of lever 280 with a dependingbent ofi ear 283 formed on arm 275. The parts are constructed andarranged so that during normal typing operations the link 281 maintainslever 280 and brake arm 275 in a clockwise position wherein the frictionpad 277 is out of operative contact with the carrier 21. When atabulating movement of the carriage is initiated, as above described,the counter clockwise rotation of lever 234 will cause lever 280 topartake of a counter clockwise stroke which is greater than that neededto swing the friction pad into contact with said rearward face ofcarrier 21. Under these conditions the spring 282 will yieldably holdsaid pad in braking engagement with the carrier and hence the typewritercarriage 11 will be prevented from acquiring speeds above apredetermined value depending on the adjustable operative tension inspring 282. At the termination of the carriage tabulating movement theclockwise movement of tab lever 234 will, through lever 280 and bent offear 283, positively swing said brake arm 275 to its normal inoperativeposition thereby leaving the carrier 21 unimpeded for subsequent typingoperations.

Referring to FIGURE 13 there is shown a back spacing apparatus forincrementally displacing the typewriter carriage in a carriage returndirection. In that the rack 16 and pinion 17, FIGURE 1, are engagedduring this operation the back space linkage is here directly operativeon the carrier 21 of the escapement mechanism 15. Secured to theescapement frame 10a is a bracket 290 which has an upwardly extendingarm 291 that is formed with an arcuate slot 292. Mounted for slidingmovement in said slot is a pin 293 which is fixedly secured to a link294 that is provided with a bent oft upwardly extending stop memberengaging finger 295. The left end, FIGURE 13, of link 294 isarticulately connected by means of a stud 296 to a bell crank 297 whichis pivotally mounted on the shaft 298. The ball crank 297 is presentlyused in the back spacing mechanism of the typewriter and hence its wellknown construction and operation need not be further particularizedhere. Suffice it to say that when a backspace operation is to be madethe bell crank 297 will be power actuated through clockwise and counterclockwise oscillatory strokes. A suitably anchored spring 300 maintainsthe link 294 in a normal left hand position determined by engagement ofstud 293 with the end of slot 292 as shown in FIGURE 13. Alsoarticulately connected to hell crank 297 by means of a stud 296 is astop member setting link 301 which extends through a suitable slot 302,FIGURE 12, formed in the rearward portion of said bracket 291. The rightend portion, FIGURE 13, of link 3111 is provided with an angularlydisposed camming surface 303 and an integral tip 304 which normallyunderlies the rearwardly extending arm 305, FIGURE 2, of a bell crank306 that is rotatably secured to said shaft 75. The upper end of thebell crank arm 307 is provided wtih a forwardly extending bent ofi ear310, FIGURES 2., 12 and 13, which has an angularly disposed camming edge311 that is located adjacent the lower rearward portion of the carrier21. A suitably anchored spring 312, FIGURE 2, normally maintains thebell crank 3116 in a counter clockwise position determined by engagementof the lower edge of said bell crank arm 305 with the tip 304 of link301 as illustrated in FIGURE 2. In this position of the bell crank thecamming edge 311 of the bell crank ear 310 lies out of the operativepath of travel of the adjacent stop members 23 and hence is inoperativeduring normal typing operations.

When a back spacing operation is to be efiected the power actuatedclockwise stroke of hell crank 297 will cause the end of finger 295 oflink 29 1 to move along an arcuate path determined by the contour ofsaid slot 292, and to engage the forward end portion of an adjacent setstop member 23 and displace the latter through an arcuate distance whichis slightly greater than the circumferential pitch of said stop members23. The resultant clockwise rotation 51, FIGURE 13, of the carrier 21and pinion 17 causes the typewriter rack 16 and carriage 11 to bedisplaced through a distance corresponding to a little more than oneincremental unit in a carriage return direction. During this action, theclockwise motion of hell crank 297 will, through link 301, cause theangular camming edge 311, FIGURE 12, of bell crank ear 310 to be swunginto the operative path of travel of the rearward end 59, FIGURE 4, ofthe adjacent unset stop member 23. In that said adjacent stop member 23will then be moving in a clockwise direction by the action of the backspacing link 2941-, as just described, the rearward end 59 of said stopwill wipe past said camming edge in swinging by the end 36 of saidstationary stop 33 and will be thereby displaced from an unset positionto a set position. As a result after the completion of the saidbackspacing move ment of the carrier 21, the said stop member 23 whichwas just moved to set position by cam edge 311 may then swing back ashort distance into operative engagement with the end 36 of stop 33 andthereby maintain the carriage in a position which is one increment unitto the right, as viewed from the front of the machine, from thatposition which it occupied just previous to the back spacing operation.After completion of the clockwise motion of hell crank 297, the springs312 and 300 will respectively urge the bell crank 3116 and link 294towards their normal positions shown in FIGURES l2 and 13 preparatoryfor subsequent typing operations or another carriage back spacingoperation.

While there is in this application specifically described one form whichthe invention may assume in practice, it will be understood that thisform of the same is shown for purposes of illustration only and that theinvention may be modified and embodied in various other forms withoutdeparting from its spirit or the scope of the appended claims.

The invention claimed is:

1. In a machine of the class described having a frame;

a carriage movably mounted on said frame; a mechanism for driving saidcarriage in at least one direction; and means for controlling the feedmovement of said carriage in said one direction under the action of saiddrive mechanism: said means comprising a carrier movably mounted on saidframe and operatively connected to said carriage; a plurality of stopmembers movably mounted on said carrier; a stop mounted on said frame;said stop members each being movable to a set position so as to becooperable with said stop thereby preventing movement of said carriagein said one direction, and to an unset position so as to by-pass saidstop thereby permitting a movement of said carriage in said onedirection; means for moving each successive stop member to a setposition as said stop members respectively approach said stop; andselectively operable means for sequentially displacing said set stopmembers to unset positions so as to successively permit said carriage tointermittently partake of predetermined feed movements in said onedirection under the action of the carriage driving mechanism.

2. Apparatus as defined by claim 1, additionally comprising a letterspacing expanding device including a second normally stationary stopmounted on said frame and adapted to cooperate With stop members thatare in set positions; said second stationary stop being formed with astop member contacting surface that is offset with respect to the normaloperative position of the correspond ing contact surface on the firstmentioned stop, and means for moving the first mentioned stop and saidsecond stop out of the path of travel of the set stop members.

3. In a typewriter having a frame; a transversely movable carriagemounted on said frame; and drive means for moving said carriage in aletter feed direction: a proportional spacing mechanism comprising acarrier movably mounted on said frame and operatively geared to saidcarriage; a plurality of stop members movably mounted on said carrier; astop mounted on said frame; each of said stop members being movable toeither a set position so as to be engageable with said stop and therebyprevent movement of said carriage, or to an unset position so as toby-pass said stop and thereby permit movement of said carriage; meansfor moving said stop members to set positions; and a plurality ofselectively operable fingers for successively displacing differentnumbers of the set stop members to unset positions for permitting saidcarriage to successively move through variable distances under theaction of said drive means.

4. In a typewriter having a frame; a carriage movably mounted on saidframe; drive means for said carriage; a plurality of type bars movablymounted in said frame and each adapted to partake of a printing stroke;and means for controlling the movement of said carriage; the lastmentioned means comprising a plurality of stop members; movable means onsaid frame for supporting said stop members; means operativelyconnecting said movable means to said carriage; a stop mounted on saidframe; said stop members each being movable to a set position so as tobe engageable with said stop thereby preventing movement of saidcarriage, and to an unset position so as to by-pass said stop therebypermitting movement of said carriage; means for moving each stop memberto a set position; and means normally operative for displacing apredetermined plurality of the set stop members to unset positions so asto permit said drive means to move said carriage through a distance theextent of which is determined by the number of said set stop memberswhich are displaced to unset positions.

5. In a machine of the class described having a frame; a carriagemovably mounted on said frame; a mechanism for driving said carriage inat least one direction; and means for controlling the feed movement ofsaid carriage in said one direction under the action of said drivemechanism: said means comprising a carrier movably mounted on said frameand operatively connected to said carriage; a plurality of stop membersmovably mounted on said carrier; a normally stationary stop mounted onsaid frame; said stop members each being movable to a set position so asto be cooperable With said normally stationary stop and thereby preventmovement of said carriage in said one direction, and to an unsetposition so as to bypass said normally stationary stop and therebypermit a movement of said carriage in said one direction; means movingeach stop member to a set position as said members respectively approachsaid stop; and a plurality of selectively operable fingers for normallydisplacing a predetermined plurality of the set stop members to unsetpositions so as to permit said carriage to intermittently partake ofpredetermined feed movements in said one direction under the action ofthe carriage driving mechanism.

6. In a machine of the class described having a frame; a carriagemovably mounted on said frame; a mechanism for driving said carriage inat least one direction; and means for controlling the feed movement ofsaid carriage in said one direction under the action of said drivemechanism: said last named means comprising a carrier movabiy mounted onsaid frame and operatively connected to said carriage; a plurality ofequally spaced stop members movably mounted on said carrier; a normallystationary stop mounted upon said frame; said stop members beingsuccessively movable to a set position to engage the stop side of saidstationary stop and thereby prevent movement of said carriage in saidone direction, and movable to an unset position so as to bypass saidnormally stationary stop to thereby permit a movement of said carriagein said one direction; means moving each stop member to a set positionadjacent the stopping side of said normally stationary stop; and meansfor displacing the set stop members to unset positions adjacent thestopping side of said stop to permit said carriage to intermittentlypartake of predetermined feed movements in said one direction under theaction of said carriage driving mechanism.

7. In a machine of the class described; a frame; a carriage movablymounted on said frame; a mechanism for driving said carriage in at leastone direction; and means for controlling the feed movement of saidcarriage in said one direction under the action of said drivingmechanism: said means comprising a disc rotatably mounted on said frameand operatively connected to said carriage; a plurality of stop membersmovably mounted on said disc; a normally stationary stop mounted on saidframe; said stop members each being movable to a set position so as tobe cooperable With said normally stationary stop and therby preventmovement of said carriage in said one direction, and to an unsetposition so as to bypass said normally stationary stop and therebypermit a movement of said carriage in said one direction; meansdisplacing each successive stop member to a set position in response tothe respective bodily movements of said members as the latter approachsaid stop; and means for displacing the initially set stop members tounset positions so as to permit the carriage driving mechanism tointermittently move said carriage in said one direction.

8. In a typewriter having a frame; a carriage movably mounted on saidframe; drive means for moving said carriage in a letter feed direction;a plurality of type bars movably mounted on said frame and each adaptedto partake of a printing stroke; and means for controlling the movementof said carriage: the last mentioned means comprising a plurality ofstop members; movable means on said frame for supporting said stopmembers; means operatively gearing said movable means to said carriage;a stop mounted on said frame; said stop members each being movable to aset position so as to be engageable with said stop thereby preventingmovement of said carriage, and to an unset position so as to by-passsaid stop thereby permitting movementof said carriage; means displacingeach successive stop member to a set position as said stop membersrespectively progressively approach said stop; and a plurality ofselectively operable means responsive to the operation of some of saidtype bars for normally displacing a predetermined plurality of the setstop members to unset positions so as to permit said drive means to movesaid carriage through a distance the extent of which is determined bythe number of said set stop members which are normally displaced tounset positions.

9. In a typewriter having a frame; a carriage movably mounted on saidframe; means for driving said carriage in a letter feed direction; and aplurality of type bars pivotally mounted in said frame and each adaptedto partake of a printing stroke: the improvement comprising a discrotatably mounted in said frame; means for operatively gearing said discto said carriage; a plurality of spaced stop members movably mounted onsaid frame adjacent said disc; said stop members each being movable to aset position so as to be engageable with said stop thereby preventingletter feeding movement of said carriage, and to an unset position so asto by-pass said stop member thereby permitting a letter feeding movementof said carriage under the action of said driving means; cam meansmounted on said frame; said cam means being constructed and arranged toprogressively move each successive stop member to a set position as saidstop members respectively approach said stop; and a plurality ofindividually operable fingers movably mounted on said frame andselectively actuated in response to the operation of each of said typebars for selectively displacing several of the set stop members to unsetpositions so as to permit said carriage to incrementally move in aletter feed direction by an amount determined by the number of said setstop members moved to said unset positions.

10. In a typewriter having a frame; a carriage movably mounted on saidframe; and drive means for moving said carriage in a letter feeddirection: the improvement comprising a disc rotatably mounted on saidframe; means operatively gearing said disc to said carriage so that alinear displacement of said carriage in a letter feeding direction isaccompanied by a rotary motion of said disc; a plurality of stop membersmovably mounted in a circular array around the periphery of said disc;said stop members being longitudinally movable in directionssubstantially parallelto-the axis of rotation of said disc; a stopmounted on said frame adjacent the periphery of said disc; said stopmembers each being movable to a set position so as to be engageable withsaid stop and thereby prevent letter feeding movement of said carriage,and to an unset position so as to by-pass said stop and thereby permitletter feeding movement of said carriage under the action of said drivemeans; a cam mounted on said frame adjacent the periphery of said disc;said cam being constructed and arranged so as to successively displacesaid stop members to their respective set positions in response to therotation of said disc produced by movement of said carriage in saidletter feed direction; a plurality of fingers movably mounted on saidframe and being operatively disposed adjacent the periphery of said discin a region between said cam and said stop; said fingers beingselectively operable to sequentially displace different numbers of theinitially set stop members to unset positions so as to permit saidcarriage to intermittently move in a letter feed direction throughvariable distances depending on the respective numbers of stop membersrespectively moved to unset positions; and cam means for successivelydisplacing stop members which are inset positions to unset positionsduring rotation of said disc produced by a return movement of saidcarriage.

11. The combination with a typewriter having a movable carriage of anescapement mechanism for permitting uniform and variable movement ofsaid carriage comprising a carrier, said carriage and said carrier beingoperatively connected whereby said carrier is urged in one l8 direction,a series of stop members mounted on said carrier for movement from afirst to a second position, stop means cooperable with one of saidseries of stop members in said first position for holding said carrieragainst movement, means for moving said one stop member and a number ofsuccessive stop members in said series to said second position, said onestop member and number of successive stop members corresponding to adesired incremental movement of said carriage, and means for restoringthe equivalent number of members moved to said second position to saidfirst position during said incremental movement.

12. Apparatus as recited in claim 11 further comprising carriagetabulating mechanism, means responsive to operation of said tabulatingmechanism for moving said stop means from a normal operative position toan inoperative position out of the path of said stop members to permittabulating advance of said carriage, and means operative upon arrest ofsaid tabulating advance of the carriage for restoring said stop means tonormal operative position.

13. Apparatus as recited in claim 12 additionally oomprising a pluralityof settable tab stops, and means responsive to operation of saidtabulating mechanism for cooperating with said settable stops forarresting said tabulating advance, said settable tab stop spacingcorresponding to the spacing between a predetermined number of said stopmembers and being always in phase with predetermined ones of said stopmembers.

14. In a business machine having a carriage, type bars, key levers, andmeans controlled by said key levers for operating said type bars, saidtype bars each bearing a type character of Varying width, a proportionalescapement mechanism for releasing said carriage after printing a letterand for stopping said carriage after the latter has travelled a distancecorresponding to the width of the letter printed, said mechanismcomprising a disc, means operatively connecting said disc with saidcarriage, stop members mounted on said disc for movement to a first anda second position, stop means adapted to cooperate with stop members insaid first position for stopping carriage movement, a plurality ofselectively operable fingers for normally moving a predetermined numberof said set stop members to said second position whereby said carriageis permitted to move a predetermined number of incremental units ofdistance, means for restoring stop members in said second position tosaid first position during letter feed movement of said carriage, amechanism for initiating a carriage tabulating movement, meansresponsive to the operation of said tabulating mechanism for swingingsaid stop means from a normal operative position to an inoperativeposition, means to arrest the tabulating movement of said carriage, andmeans responsive to the operation of the last mentioned means forswinging said stop means back to its normal operative position andlocking the same in said operative position.

15. In a typewriter; a frame; a carriage movably mounted on said frame;drive means for moving said carriage in a letter feeding direction; aplurality of settable stop members; means mounted on said frame formovably supporting said stop members; means for operatively gearing thelast mentioned means to said carriage; a stop mounted on said frame,said stop being movable to a normal operative position and to aninoperative position; each of said stop members being movable to a setposition so as to be engageable with said operatively positioned stopthereby preventing a letter feeding movement of said carriage, and to anunset position so as to by-pass said operatively positioned stop therebypermitting a letter feeding movement of said carriage; means forsuccessively displacing said stop members to set positions as said stopmembers respectively approach said stop; means for displacing saidinitially set stop members to unset positions to thereby permit letterfeeding movement of said carriage under the action of said drive means;means for moving said stop to an inoperative position out of the path ofmovement of the stop members which have been displaced to set positionsso as to initiate a tabulating movement of said carriage; means forarresting the tabulating movement of said carriage; and means responsiveto the operation of the carriage arresting means for restoring said stopto its normal operative position.

16. In a typewriter; a frame; a carriage movably mounted on said frame;drive means for moving said carriage in a letter feeding direction; aplurality of settable stop members; means mounted on said frame formovably supporting said stop members; means for operatively gearing thelast mentioned means to said carriage; a stop mounted on said frame,said stop being movable to a normal operative position and to aninoperative position; each of said stop members being movable to a setposition so as to be engageable with said operatively positioned stopthereby preventing letter feeding movement of said carriage, and to anunset position so as to by-pass said operatively positioned stop therebypermitting letter feeding movement of said carriage; means successivelydisplacing said stop members to set positions in response to theapproach; of the latter towards said stop; means for selectivelydisplacing said initially set stop members to unset positions to therebypermit letter feeding movement of said carriage under the action of saiddrive means; means for moving said stop to an inoperative position outof the operative path of movement of the stop members which have beendisplaced to set positions so as to initiate a tabulating movement ofsaid carriage; means for arresting the tabulating movement of saidcarriage; means for retaining said stop in its inoperative positionduring said carriage tabulating movement; and means responsive to thetermination of said carriage tabulating movement for disabling saidcarriage arresting means and for returning said stop to its normaloperative position thereby restoring control of carriage movements tosaid stop members and said stop, the returning of said stop to itsnormal operative position being effective to move at least one of theset stop members to an unset position.

17. Apparatus as defined by claim 15, additionally comprising a movabletabulating braking means adapted to be moved from an inoperative to anoperative position so as to frictionally engage the stop membersupporting means, and means for moving said braking means to anoperative position when said stop is moved to an inoperative positionand for moving said braking means to an inoperative position when saidstop is moved to an operative position.

18. Apparatus as defined by claim 1, additionally comprising anexpanding means comprising a second normally stationary stop mounted onsaid frame; said second stop having an abutment surface which normallylies in the operative path of travel of said set stop member and whichis offset, circumferentially of said carrier, with respect to the stopmember engaging surface of the first mentioned stop so as to be operableto control the letter feed movement of said carriage when said firstmentioned stop is moved to its inoperative position.

19. Apparatus as defined by claim 1, additionally comprising cam meansfor successively displacing the set stop members to unset positionsduring rotation of said carrier produced by a return movement of saidcarriage.

20. Apparatus as defined by claim 10, additionally comprising a secondcam means for successively displacing stop members which are in unsetpositions to set positions during rotation of said disc produced by saidreturn movement of said carriage.

21. Apparatus as defined by claim 1, additionally comprising a carriageback spacing mechanism having a power operated member adapted to engageone of the stop members on said carrier and rotatably displace thelatter a short distance in a carriage return direction, and meansresponsive to this displacement for moving at least one other of saidstop members from unset to set position so that this stop member maysubsequently swing into carriage restraining engagement with said stop.

References Cited in the file of this patent UNITED STATES PATENTS1,054,875 Smith Mar. 4, 1913 1,286,186 Miller Nov. 26, 1918 2,303,878Helmond Dec. 1, 1942 2,439,470 Jackson Apr. 13, 1948 2,518,166 MillerAug. 18, 1950 2,794,530 Liebmann June 4, 1957 FOREIGN PATENTS 529,261Italy June 21, 1955

